Method, device and computer-readable storage medium containing instructions for determining applicable traffic rules for a motor vehicle

Abstract

Procedure for determining applicable traffic rules for a motor vehicle (40), comprising the steps: - Transmitting (11) at least a history of positions and direction of movement of the motor vehicle (40) to a backend (90) by means of a transmission device (23) of the motor vehicle (40); and - Receiving (12) information on traffic rules applicable at the position of the motor vehicle (40) by the transmission device (23); wherein the transmission (11) of at least a history of positions and direction of movement of the motor vehicle (40) to the backend (90) is carried out cyclically or depending on information on the validity of the traffic rules contained in the information on the traffic rules applicable at the position of the motor vehicle (40), and wherein in the history of positions positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

Description

[0001] The present invention relates to methods, devices, and a computer-readable storage medium containing instructions for determining applicable traffic rules for a motor vehicle. The invention further relates to a motor vehicle in which a method or device according to the invention is used.

[0002] In modern vehicles, drivers are often provided with information about road signs, current speed limits, or no-overtaking zones, for example, by displaying it on an instrument panel or head-up display. This information can also be used by various control units within the vehicle, such as for automatic speed control or to warn of illegal overtaking maneuvers. The reliable availability of such information is essential for autonomous and semi-autonomous driving.

[0003] Currently, there are essentially two approaches to providing information on traffic signs or the traffic rules currently applicable to a vehicle. The first approach is based on the use of navigation maps that include traffic signs. The second approach involves traffic sign recognition using camera systems.

[0004] For example, DE 10 2013 013 799 A1 describes an assistance system that supports a driver during an overtaking maneuver by determining, based on the speed difference to the vehicle being overtaken and the remaining overtaking distance, whether the maneuver can be completed safely. The determination of the remaining overtaking distance can be carried out using traffic sign recognition or GPS-based map data.

[0005] German patent DE 10 2007 034 505 A1 describes a method for traffic sign recognition. Based on provided image data, traffic sign recognition is performed using a country-specific traffic sign database with at least partially country-specific classification characteristics or classification procedures. If the traffic sign recognition is of low quality, the recognition process is repeated using stored image regions containing detected traffic signs and an alternative country-specific traffic sign database. This process is repeated until the traffic sign recognition result is of sufficient quality. The country-specific traffic sign database for which at least sufficient quality has been determined is then pre-selected for further traffic sign recognition operations.

[0006] A method for providing traffic sign information is known from DE 10 2008 043 756 A1. In a first step, traffic sign data is stored in the vehicle. Subsequently, the stored traffic sign data is assigned to the vehicle's current position. Based on the traffic sign data assigned to the vehicle's current position, traffic sign information is then provided. This traffic sign data can be queried section by section from an online service based on the vehicle's position information.

[0007] One disadvantage of camera-based solutions is their limited range, meaning that predictive detection of traffic signs is only possible to a limited extent. Furthermore, the reliability of the recognition decreases with increasing vehicle speed.

[0008] One disadvantage of solutions based on navigation maps is that these maps must always be up-to-date, meaning they require continuous updates, for example, through online updates. The necessary maps incur licensing costs and are usually only sold together with a navigation function. This results in additional costs for the user.

[0009] German patent DE 10 2015 219 467 A1 describes a method for operating a central server that enables the centralized management of traffic rule maps. When a vehicle approaches an intersection or the driver wants to initiate an overtaking maneuver, a request for a traffic rule map is sent to the server. The server then sends the requested traffic rule map to the vehicle. The server can also continuously send traffic rule maps.

[0010] WO 2011 / 044922 A1 describes a navigation device comprising a receiver for receiving position signals, a memory for storing map data, an output device, and a processor. The map data includes a map of navigable paths and features along those paths, such as rights of way granted to different users. The processor determines the current position on the navigable paths from the position signals. Based on this current position, it determines whether the navigation device is likely to cross the right-of-way of another user on the navigable paths. If so, the output device issues a warning.

[0011] German patent DE 10 2013 225 497 A1 describes a method for supporting data communication between a vehicle's computer and at least one external service server using a support system separate from both the vehicle and the service server. This support system communicates with the vehicle's computer and the service server. The vehicle's computer and the service server may use different digital maps and georeferencing methods. Instead of a specific georeference, the service server may only transmit a code along with the associated information. This code is then received by the vehicle, and the computer checks whether a map reference from a digital map or a georeference is already stored in memory for this code.If this is not the case, the vehicle transmits this code with a request message to the assistance system, which then transmits the requested georeference or map reference to the vehicle. Such a request message only needs to be transmitted once for each code, as the data can be stored in the vehicle's computer unit's memory for later use.

[0012] German patent DE 102 10 546 A1 describes a method for automated vehicle guidance in which infrastructure data is wirelessly transmitted to the vehicle and commands for vehicle guidance are calculated based on this infrastructure data. The infrastructure data for at least one immediately upcoming section of the route is loaded into the vehicle's own memory. A precise positioning system continuously determines the vehicle's current position. The commands are then calculated based on the position data and the stored infrastructure data.

[0013] EP 2 843 639 A1 describes a method for transmitting location information via a vehicle's communication device. In this method, the location of the communication device is continuously identified. Location information indicating the device's position is transmitted at intervals. The transmission interval is set according to the communication device's location.

[0014] It is an object of the invention to show further solutions for determining applicable traffic rules for a motor vehicle that enable a reliable provision of the desired information without the need to keep a map in the motor vehicle.

[0015] This problem is solved by a method having the features of claim 1, by a computer-readable storage medium with instructions according to claim 10, and by a device having the features of claim 11 or 12. Preferred embodiments of the invention are the subject of the dependent claims.

[0016] According to a first aspect of the invention, a method for determining applicable traffic rules for a motor vehicle comprises the following steps: - Transmitting at least a history of the vehicle's positions and direction of movement to a backend via a transmission device in the vehicle; and - Receiving information on traffic rules applicable at the position of the motor vehicle by the transmission device; wherein the transmission of at least a history of positions and a direction of movement of the motor vehicle to the backend is carried out cyclically or depending on information on the validity of the traffic rules contained in the information on the traffic rules applicable at the position of the motor vehicle, and wherein in the history of positions positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0017] According to a further aspect of the invention, a computer-readable storage medium contains instructions which, when executed by a computer, cause the computer to perform the following steps to determine applicable traffic rules for a motor vehicle: - Transmitting at least a history of the vehicle's positions and direction of movement to a backend via a transmission device in the vehicle; and - Receiving information on traffic rules applicable at the position of the motor vehicle by the transmission device; wherein the transmission of at least a history of positions and a direction of movement of the motor vehicle to the backend is carried out cyclically or depending on information on the validity of the traffic rules contained in the information on the traffic rules applicable at the position of the motor vehicle, and wherein in the history of positions positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0018] The term "computer" is to be understood broadly. In particular, it also includes control units and other processor-based data processing devices.

[0019] According to another aspect of the invention, a device for determining applicable traffic rules for a motor vehicle comprises: - a transmission device for transmitting at least a history of the vehicle's position and direction of movement to a backend and for receiving information on the traffic rules applicable at the vehicle's position; and - a data processing unit for evaluating the information on the traffic rules applicable at the position of the motor vehicle; wherein the transmission device is configured to transmit at least a history of positions and a direction of movement of the motor vehicle to the backend cyclically or depending on information on the validity of the traffic rules contained in the information on the traffic rules applicable at the position of the motor vehicle, and wherein in the history of positions positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0020] With regard to a system that can be used in a motor vehicle, or a device that can be installed in a motor vehicle, only the vehicle's position and direction of travel are recorded and transmitted to a backend system. Based on this information, the backend determines the applicable traffic regulations, which are then transmitted to the vehicle. The vehicle therefore requires neither sensors for detecting traffic signs nor special, constantly updated map information, resulting in significant cost savings. The querying of traffic regulations can optionally be performed cyclically, i.e., at regular temporal or spatial intervals, or depending on information regarding the validity of the traffic regulations. In this way, only manageable amounts of data need to be transmitted, making data transmission between the vehicle and the backend very efficient.

[0021] According to the invention, a history of the vehicle's positions is transmitted to the backend. This position history, i.e., a trace of past waypoints, is extremely helpful for correctly assigning the vehicle's position to a road, and in particular to the correct lane in the case of multi-lane roads. The position history preferably includes positions immediately before and after a lane change or positions involving steering angle changes.

[0022] According to another aspect of the invention, a method for determining applicable traffic rules for a motor vehicle comprises the following steps: - Receiving at least one history of positions and direction of movement of the motor vehicle; - Determining information on the traffic rules applicable at the location of the motor vehicle; and - Transmitting information on the traffic rules applicable at the vehicle's position to the vehicle; wherein the information on the traffic rules applicable at the vehicle's position includes information on the validity of the traffic rules, and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0023] According to a further aspect of the invention, a computer-readable storage medium contains instructions which, when executed by a computer, cause the computer to perform the following steps to determine applicable traffic rules for a motor vehicle: - Receiving at least one history of positions and direction of movement of the motor vehicle; - Determining information on the traffic rules applicable at the location of the motor vehicle; and - Transmitting information on the traffic rules applicable at the vehicle's position to the vehicle; wherein the information on the traffic rules applicable at the vehicle's position includes information on the validity of the traffic rules, and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0024] The term "computer" is to be understood broadly here as well. In particular, it also includes workstations, distributed systems, and other processor-based data processing devices.

[0025] According to another aspect of the invention, a device for determining applicable traffic rules for a motor vehicle comprises: - a transmission device for receiving at least one history of the motor vehicle's position and direction of movement and for transmitting information on the traffic rules applicable at the motor vehicle's position to the motor vehicle; and - a computing unit for determining the information on the traffic rules applicable at the position of the motor vehicle; wherein the computing unit is configured to provide the information on the traffic rules applicable at the position of the motor vehicle with information on the validity of the traffic rules, and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted.

[0026] With regard to a process that can be used in a backend, or a device that can be installed in a backend, the backend receives only a history of the vehicle's position and direction of travel. Based on this information, the backend determines the applicable traffic regulations, which are then transmitted to the vehicle. To keep the required data volume low, the backend also determines information about the validity of the traffic regulations and transmits this information to the vehicle. The vehicle can then query the traffic regulations based on this validity, so that no more queries than necessary are sent to the backend.

[0027] According to one aspect of the invention, determining the information on the traffic rules applicable at the location of the motor vehicle comprises the following steps: - Assigning the position of the motor vehicle to a road in a road network; - Determining the traffic rules applicable to the road at the vehicle's position; and - Determining at least one distance in the road network until a change in the applicable traffic rules.

[0028] Once the vehicle's position has been assigned to a road within a road network, i.e., on a map, the desired traffic regulations can be directly retrieved from the map data. Furthermore, potential routes can be checked against the map for changes in traffic regulations. This makes it easy to determine up to which future vehicle positions no further query of the traffic regulations by the vehicle is necessary.

[0029] According to one aspect of the invention, the information regarding the validity of traffic regulations includes an indicator that shows whether the vehicle's position is in or adjacent to an intersection. For transmitting a history of the vehicle's position and direction of movement to the backend, a higher cycle frequency is preferably used when the indicator is present. This approach increases the reliability of the described solutions in intersection areas.

[0030] According to one aspect of the invention, the information regarding the validity of traffic regulations describes a spatial validity, in particular a spatial validity dependent on a travel route. In this case, the transmission of at least a history of the vehicle's position and direction of travel to the backend is performed again when the spatial validity expires. This approach requires very few queries, resulting in a very low data volume. Furthermore, no continuous data connection is necessary. The spatial validity can be defined, for example, by the minimum distance until a change in traffic regulations occurs; alternatively, multiple distances for different possible routes can be transmitted.

[0031] According to one aspect of the invention, the information on the traffic rules applicable at the vehicle's location includes detailed information on at least one intersection. Using this detailed information, e.g., an intersection model or an intersection network, a certain degree of predictive capability can be achieved in the event of latency in the query to the backend, thus further increasing the reliability of the method.

[0032] According to one aspect of the invention, the traffic rules applicable at the location of the motor vehicle describe a speed limit, right-of-way rules, or a no-overtaking rule. This covers typical cases of traffic rules that are valid over longer stretches of road and are therefore particularly suitable for the application of the described solutions.

[0033] Preferably, a method or device according to the invention is used in a vehicle, in particular a motor vehicle.

[0034] Further features of the present invention will become apparent from the following description and the attached claims in conjunction with the figures. Fig. Figure 1 schematically shows a procedure for determining applicable traffic rules for a motor vehicle from the perspective of the motor vehicle; Fig. 2 shows a first embodiment of a device for determining applicable traffic rules for a motor vehicle, which can be installed in a motor vehicle; Fig. Figure 3 shows a second embodiment of a device for determining applicable traffic rules for a motor vehicle, which may be installed in a motor vehicle; Fig. Figure 4 schematically represents a motor vehicle in which a solution according to the invention is implemented; Fig. Figure 5 schematically shows a procedure for determining applicable traffic rules for a motor vehicle from the perspective of a backend; Fig. Section 6 shows further details on how to determine the traffic rules applicable at the location of the motor vehicle; Fig. Figure 7 shows a first embodiment of a device for determining applicable traffic rules for a motor vehicle, which may be installed in a backend; Fig. Figure 8 shows a second embodiment of a device for determining applicable traffic rules for a motor vehicle, which may be installed in a backend; Fig. Figure 9 illustrates a system for determining applicable traffic rules for a motor vehicle; Fig. Figure 10 illustrates two advantageous algorithms that are used in the system of Fig. 9 can be implemented; Fig. Figure 11 shows an intersection model that can be transmitted to a motor vehicle as part of information on applicable traffic rules; Fig. Figure 12 illustrates a first iteration step in determining the validity distance of a speed limit; Fig. Figure 13 illustrates a second iteration step in determining the validity distance of a speed limit; and Fig. Figure 14 illustrates a final result of determining the validity distance of a speed limit.

[0035] To better understand the principles of the present invention, embodiments of the invention are explained in more detail below with reference to the figures. It is understood that the invention is not limited to these embodiments and that the described features can also be combined or modified without leaving the scope of protection of the invention as defined in the appended claims.

[0036] Fig. Figure 1 schematically illustrates a procedure for determining applicable traffic rules for a motor vehicle from the vehicle's perspective. First, the vehicle's position and direction of travel are determined. A history of the vehicle's position and direction of travel is then transmitted to a backend system by a transmission device within the vehicle. Positions immediately before and after a lane change, or positions involving steering angle changes, are given priority in the position history. Finally, in response to the information transmitted to the backend, the transmission device receives information about the traffic rules applicable at the vehicle's position, such as speed limits, right-of-way rules, or no-overtaking zones.The transmission of the vehicle's position and direction of travel to the backend occurs cyclically or depending on information regarding the validity of traffic regulations, which is contained in the data on the traffic rules applicable at the vehicle's position. This validity information can, for example, include an indicator indicating that the vehicle's position is in or adjacent to an intersection. The query of the applicable traffic regulations at the backend can then be performed with a higher cycle frequency when this indicator is present. Similarly, the validity information can describe spatial validity, in particular, spatial validity dependent on a travel route. In this case, the query of the applicable traffic regulations at the backend is preferably performed again only when the spatial validity expires.

[0037] Furthermore, the information on the traffic rules applicable at the vehicle's location may include detailed information on intersections.

[0038] Fig. Figure 2 shows a simplified schematic representation of a first embodiment of a device 20 for determining applicable traffic rules for a motor vehicle, which can be installed in a motor vehicle. The device 20 has an input 21 for receiving information on the position and direction of travel of the motor vehicle, for example from a navigation system, or data that allows the determination of the position and direction of travel of the motor vehicle. A tracking unit 22 extracts or determines the position and direction of travel of the motor vehicle from the received data and selects the data to be transmitted to a backend. A transmission device 23 transmits the selected data, i.e., a history of positions and a direction of travel of the motor vehicle, to the backend.In the position history, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted. Furthermore, the transmission device 23 receives information from the backend regarding the traffic regulations applicable at the vehicle's position, such as speed limits, right-of-way rules, or no-overtaking zones. The transmission device 23 is configured to transmit the vehicle's position and direction of travel to the backend cyclically or depending on information about the validity of the traffic regulations contained in the data about the traffic regulations applicable at the vehicle's position. This validity information can, for example, include an indicator that shows the vehicle is in or adjacent to an intersection.The query of the applicable traffic regulations at the backend can then be performed with an increased cycle frequency if the indicator is present. Similarly, the validity information can describe spatial validity, in particular spatial validity dependent on a travel route. In this case, the query of the applicable traffic regulations at the backend is preferably only performed again when the spatial validity expires. Furthermore, the information on the traffic regulations applicable at the vehicle's location can include detailed information on intersections. A data processing unit 24 evaluates the received information on the traffic regulations applicable at the vehicle's location. The data generated by the data processing unit 24 is preferably made available for further use via an output 26 of the device 20.The tracking unit 22, the transmission device 23, and the data processing unit 24 can be controlled by a control unit 25. Settings of the tracking unit 22, the transmission device 23, the data processing unit 24, or the control unit 25 can be changed via a user interface 28. The data generated in the device 20 can be stored in a memory 27 of the device 20, for example, for later evaluation or for use by the components of the device 20. The tracking unit 22, the transmission device 23, the data processing unit 24, and the control unit 25 can be implemented as dedicated hardware, for example, as integrated circuits. Of course, they can also be partially or completely combined or implemented as software running on a suitable processor, for example, a GPU.Input 21 and output 26 can be implemented as separate interfaces or as a combined bidirectional interface.

[0039] Fig. Figure 3 shows a simplified schematic representation of a second embodiment of a device 30 for determining applicable traffic regulations for a motor vehicle, which can be installed in a motor vehicle. The device 30 has a processor 32 and a memory 31. For example, the device 30 is a computer or a control unit. Instructions are stored in the memory 31 which, when executed by the processor 32, cause the device 30 to perform the steps according to one of the described methods. The instructions stored in the memory 31 thus embody a program executable by the processor 32, which implements the method according to the invention. The device has an input 33 for receiving information, for example, data acquired by sensors of the motor vehicle. Data generated by the processor 32 is provided via an output 34.Furthermore, they can be stored in memory 31. Input 33 and output 34 can be combined into a bidirectional interface.

[0040] The processor 32 can comprise one or more processor units, such as microprocessors, digital signal processors, or combinations thereof.

[0041] The memory elements 27, 31 of the described embodiments can have both volatile and non-volatile memory areas and can include a wide variety of storage devices and storage media, for example hard disks, optical storage media or semiconductor memory.

[0042] Fig. Figure 4 schematically depicts a motor vehicle 40 in which a solution according to the invention is implemented. The motor vehicle 40 includes, among other things, a navigation system 41 and environmental sensors 42, for example, a camera system. The data acquired by the navigation system 41 and, optionally, by the environmental sensors 42 are transmitted via a network 43 to a device 20 for determining the applicable traffic regulations for the motor vehicle. They can also be stored in a memory 44 of the motor vehicle 40. When required, the data is transmitted from the device 20 to a backend for evaluation via a communication unit 45. The information on the traffic regulations applicable to the motor vehicle, transmitted by the backend in response to the sent data, is communicated to the driver via a user interface 47, for example, an infotainment system with a display device.In addition, they can be made available to a driver assistance system 46 of the motor vehicle 40, for example for automatic control of the vehicle speed.

[0043] Fig. Figure 5 schematically illustrates a procedure for determining applicable traffic rules for a motor vehicle from a backend perspective. In a first step, at least a history of the vehicle's position and direction of travel are received.50 In the position history, positions immediately before and after a lane change or positions with steering angle changes are given priority. Based on the received information, details of the traffic rules applicable at the vehicle's position are then determined,51 for example, information on a speed limit, right-of-way, or overtaking prohibition. The details of the traffic rules applicable at the vehicle's position include information on the validity of the traffic rules.The validity information may, for example, include an indicator stating that the vehicle's position is in or adjacent to an intersection. Similarly, the validity information may describe spatial validity, in particular route-dependent spatial validity. Furthermore, the information on the traffic rules applicable at the vehicle's position may include detailed information on intersections. Finally, the information on the traffic rules applicable at the vehicle's position is transmitted to the vehicle.52

[0044] Fig. Figure 6 shows further details on determining the traffic rules applicable at the vehicle's location. As a first step, the vehicle's location is assigned to a road within a road network. Then, the traffic rules applicable to that road at the vehicle's location are determined. In addition, at least one validity distance is determined, i.e., the distance within the road network until a change in the applicable traffic rules.

[0045] Fig. Figure 7 shows a simplified schematic representation of a first embodiment of a device 70 for determining applicable traffic rules for a motor vehicle, which can be installed in a backend. The device 70 has a first interface 71 via which a transmission device 72 can receive information on at least one history of positions and one direction of movement of the motor vehicle. In the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferably transmitted. Via the first interface, the transmission device 72 can also transmit information on traffic rules applicable at the motor vehicle's position to the motor vehicle, for example, information on a speed limit, right-of-way, or a no-overtaking rule.Based on the information received by the transmission device 72, a positioning unit 73 locates the motor vehicle on a map. The map can be provided by an external database via a second interface 76. Based on the location, a processing unit 74 determines the required information on the traffic rules applicable at the motor vehicle's position. The processing unit 74 is configured to supplement the information on the traffic rules applicable at the motor vehicle's position with information on the validity of the traffic rules. The validity information can, for example, include an indicator stating that the motor vehicle's position is in or adjacent to an intersection. Similarly, the validity information can describe spatial validity, in particular, spatial validity dependent on a travel route.Furthermore, the information on the traffic regulations applicable at the vehicle's location can include detailed information on intersections. The transmission device 72, the positioning unit 73, and the processing unit 74 can be controlled by a control unit 75. Settings of the transmission device 72, the positioning unit 73, the processing unit 74, or the control unit 75 can be changed via a user interface 78. The data generated in the device 70 can be stored in a memory 77 of the device 70, for example, for later evaluation or for use by the components of the device 70. The transmission device 72, the positioning unit 73, the processing unit 74, and the control unit 75 can be implemented as dedicated hardware, for example, as integrated circuits.Of course, they can also be partially or fully combined, or implemented as software running on a suitable processor, such as a GPU. The first interface 71 and the second interface 76 can be implemented as separate interfaces or as a combined interface.

[0046] Fig. Figure 8 shows a simplified schematic representation of a second embodiment of a device 80 for determining applicable traffic regulations for a motor vehicle, which can be installed in a backend. The device 80 comprises a processor 82 and a memory 81. For example, the device 80 is a computer or a workstation. Instructions are stored in the memory 81 which, when executed by the processor 82, cause the device 80 to perform the steps according to one of the described methods. The instructions stored in the memory 81 thus embody a program executable by the processor 82, which implements the method according to the invention. The device has an input 83 for receiving information, for example, from a data packet transmitted by a motor vehicle. Data generated by the processor 82 is provided via an output 84.Furthermore, they can be stored in memory 81. Input 83 and output 84 can be combined into a bidirectional interface.

[0047] The processor 82 can comprise one or more processor units, such as microprocessors, digital signal processors, or combinations thereof.

[0048] The memory elements 77, 81 of the described embodiments can have both volatile and non-volatile memory areas and can include a wide variety of storage devices and storage media, for example hard disks, optical storage media or semiconductor memory.

[0049] A preferred embodiment of the invention will now be described with reference to the Fig. Sections 9 to 14 will explain this. The example shows how a speed limit is determined for the vehicle. The same principle can also be used for right-of-way rules or overtaking bans. When applied to right-of-way rules, the currently valid speed is not transmitted, but rather the status of the road, for example, priority or subordinate, as well as the distance of validity. Regarding overtaking bans, the permissibility of overtaking maneuvers is transmitted along with the distance of validity, for example, permitted, prohibited, prohibited for certain vehicle classes, or prohibited with exceptions.

[0050] Fig. Figure 9 illustrates a system for determining applicable traffic rules for a motor vehicle 40. The system comprises the motor vehicle 40 and a backend 90. In addition to a device 20 for determining applicable traffic rules, the motor vehicle 40 has a navigation system 41, a driver assistance system 46, and a user interface 47.

[0051] The backend comprises at least one device 70 for determining applicable traffic rules and a database 91 containing map data and traffic rule information. The map data can be in NDS format (NDS: Navigation Data Standard). The vehicle 40 transmits its current position, along with a trace (i.e., at least one past waypoint) and its direction, to the backend 90. This data can be provided, for example, by the navigation system 41. The backend 90 uses this information to assign the vehicle 40 to a road. For this purpose, the map data from the database 91 is provided to the device 70 for determining applicable traffic rules. Based on this assignment, the currently valid speed limit for the vehicle 40 is determined and transmitted to the vehicle 40.Furthermore, a validity distance for the speed limit and at least one subsequent speed limit can be determined and transmitted. This can be done, in particular, taking into account possible route decisions. The current speed limit determined by the device 20 from the received data can be displayed on a screen of the user interface 47. In addition, the speed limit and, if applicable, subsequent speed limits can be made available to the driver assistance system 46. If the subsequent speed limits are route-dependent, information on the selected route can be provided by the navigation system 41 as needed. Furthermore, the navigation system 41 can be instructed to restart position tracking as soon as a request for applicable traffic regulations has been transmitted to the backend 90.

[0052] Fig. 10 illustrates two advantageous algorithms 92, 93, which are used in the system of Fig. 9 can be implemented. A first algorithm 92 is implemented in the database 91. However, it can also be executed by the device 70 for determining applicable traffic rules or by a dedicated component of the backend 90. Algorithm 92 is a search algorithm. This determines the speed limit applicable at the position of the motor vehicle 40. In addition, the search algorithm can be able to determine a minimum, possibly route-dependent, minimum distance until a change in the speed limit. This will be explained further below using the Fig. Sections 12 to 14 explain this. A further algorithm 93 is implemented in the device 20 located in the motor vehicle 40 for determining applicable traffic regulations. This algorithm 93 can also alternatively be executed by a dedicated component of the motor vehicle 40. In particular, the algorithm selects those past waypoints that are to be transmitted to the backend 90. Preferably, the past positions are stored in a ring buffer, so that the newest waypoint always replaces the oldest waypoint already stored. In this way, only a small amount of storage space is required while simultaneously providing a continuous trace to the current position. The past waypoints should have a certain minimum interval between them to be meaningful.Waypoints immediately before and after a lane change are particularly important for correctly assigning the vehicle's position to a road, and especially to the correct lane on multi-lane roads. These waypoints are therefore preferentially transmitted to backend 90. Since cornering maneuvers can be readily identified by the steering angle, information about the steering angle profile can also be provided. Positions with changes in the steering angle, such as a curve entry, apex, or exit, are particularly relevant. It is also possible to transmit the path curvature, which can be calculated from the steering angle, for each waypoint. Furthermore, the detected lane markings (dashed, solid, double line, none) can be transmitted. This information allows for further improvement of the assignment.

[0053] Querying the applicable traffic rules at Backend 90 can be implemented in various ways, some of which are explained below.

[0054] According to an initial implementation variant, the vehicle 40 cyclically queries the backend 90 for the current speed limit. This cyclical query can be performed at a constant frequency, for example, 1 Hz, or at constant intervals, for example, every 0.5 m. This ensures that the vehicle is always informed about the current speed limit, but generates a considerable amount of data and also requires a virtually continuous data connection.

[0055] According to a second implementation variant, vehicle 40 also queries backend 90 cyclically. However, if vehicle 40 is in or near an intersection, backend 90 sends an indicator, in addition to the speed limit, to signal the presence of an intersection. In this case, vehicle 40 queries backend 90 more frequently until the indicator is reset. This variant increases reliability in intersection areas but generates a slightly larger data volume than the first implementation variant. Furthermore, it also requires a near-continuous data connection.

[0056] According to another implementation variant, vehicle 40 initially queries backend 90 for the current speed limit. Backend 90 uses search algorithm 92 to determine both the current speed limit and the minimum distance until the speed limit changes. Both pieces of information are transmitted to vehicle 40. Vehicle 40 tracks its route, for example, using vehicle sensors, and queries backend 90 again for the speed limit when it reaches the transmitted minimum distance. This variant requires very few queries, resulting in a very low data volume. Furthermore, a continuous data connection is not necessary. Instead of the minimum distance until the speed limit changes, multiple distances for different possible routes can also be transmitted.In other words, the shortest distance to a change in the speed limit is determined based on the direction condition of the first intersection encountered. For example, if vehicle 40 turns left at the first intersection 500 m away, the next change is at a distance of 525 m. If vehicle 40 continues straight ahead at the first intersection 500 m away, the next change is at a distance of 751 m. If vehicle 40 turns right at the first intersection 500 m away, the next change is at a distance of 612 m. In this case, vehicle 40 monitors not only the distance traveled but also the chosen route.

[0057] According to another variant, in addition to the current speed limit and the distances until a speed limit change, the backend 90 transmits a simple intersection model. An example of such an intersection model is shown in Fig. Figure 11 illustrates this. The intersection is represented by a circle, which depicts the intersection area. The outgoing arms of the intersection are represented by their position on the circle and by the direction of the arm. For example, the position on the circle is given by its degree relative to the center of the intersection, while the direction of the arm is given by its compass direction in degrees. Vehicle 40 can decide which arm of the intersection to drive on based on its own direction. An alternative intersection model uses GPS points to represent the arms of the intersection. By comparing its position with the GPS points, vehicle 40 can determine which arm of the intersection it belongs to. Furthermore, backend 90 can transmit an intersection network for a defined radius. Vehicle 40 then automatically locates itself within this network and determines the current speed limit.Using intersection models or the intersection network, a certain degree of foresight can be achieved in the event of latency in the request to the backend, thus increasing the reliability of the process.

[0058] Fig. Figure 12 illustrates a first iteration step in determining the validity distance of a speed limit. A section of a road network is shown, with roads represented by solid and dashed lines. The type of dashed line represents the corresponding speed limit. Roads with a solid line are irrelevant to the vehicle's current position. The search within the road network is analogous to a tree search. The road network branches out in many directions. The shortest path to a speed change within this network is sought. The vehicle is located at position P, represented by a circle. The arrow inside the circle represents the direction of travel. Another circle, VP, indicates a previous position of the vehicle.The vehicle is currently located on a section of road between two intersections "1" and "2", which could be the vehicle's future positions (ZP). The speed limit on this section of road is 30 km / h. First, the distance to the next intersection "1" in the direction of travel is determined. Additionally, the distance to the next intersection "2" in the opposite direction of travel is determined, assuming a U-turn at the next intersection "1" in the direction of travel.

[0059] In this example, the distance to intersection "1" is 150 m, and the distance to intersection "2" is 450 m. The speed limit does not change on the road sections leading up to these two intersections. Therefore, the minimum distance until a speed limit changes is always greater than 150 m. The current road section is now marked as already used for the search.

[0060] Fig. Figure 13 illustrates a second iteration step in determining the validity distance of a speed limit. Since no change in the speed limit was found, the search continues for further intersections where the speed limit might change. Starting from the intersections found in the first iteration, five more intersections, "1" to "5", can be reached. Road segments already used are disregarded in the search, provided the speed limit applies in both directions and the current route is shorter than the previously used route. The distance to intersections "1", "2", and "5" is 200 m each, the distance to intersection "3" is 250 m, and the distance to intersection "4" is 270 m. The speed limit does not change on the road segments leading up to these intersections.The minimum distance until a speed limit changes is therefore always greater than 350 m, i.e., the distance from the starting position P to intersections "1" or "2". The current road segments are now marked as already used for the search.

[0061] Fig. Figure 14 illustrates a final result of determining the validity distance of a speed limit. After several iterations, the search result is as follows: At intersection "1", the speed limit changes to 60 km / h after a total of 550 m. At intersection "3", the speed limit changes to 50 km / h after a total of 700 m. At intersection "4", the speed limit changes to 50 km / h after a total of 720 m. At intersection "5", the speed limit changes to 5 km / h after a total of 650 m. Reference symbol list 10 Determining position and direction of movement 11. Transmitting position and direction of movement 12 Receipt of information on applicable traffic regulations 20 Device Entrance 21 22 tracking units 23 Transmission device 24 Data processing unit 25 Control unit 26 Exit 27 storage 28 User interface 30 Device 31 storage 32 processor 33 Entrance 34 Exit 40 motor vehicle 41 Navigation system 42 Environmental sensors 43 Network 44 storage 45 Communication unit 46 Driver assistance systems 47 User interface 50 Receiving position and direction of movement 51 Determining information on applicable traffic rules 52. Submitting information on applicable traffic rules 60 Assigning the position to a street 61 Determining the traffic rules applicable to the road 62 Determining the validity distance of the applicable traffic rules 70 Device 71 First interface 72 Transmission device 73 Location unit 74 computing units 75 Control unit 76 Second interface 77 storage 78 User interface 79 database 80 Device 81 storage 82 processor Entrance 83 84 Exit 90 Backend 91 Database 92 Search algorithm 93 Algorithm P Position VP Previous Position ZP Future Position

Claims

[1] Method for determining applicable traffic rules for a motor vehicle (40), comprising the steps: - transmitting (11) at least one history of positions and a direction of movement of the motor vehicle (40) to a backend (90) by a transmission device (23) of the motor vehicle (40); and - Receiving (12) information on traffic regulations applicable at the position of the motor vehicle (40) by the transmission device (23); wherein the transmission (11) of at least one history of positions and a direction of movement of the motor vehicle (40) to the backend (90) takes place cyclically or as a function of information on a validity of the traffic regulations contained in the information on the traffic regulations applicable at the position of the motor vehicle (40), and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted. [2] Method for determining applicable traffic rules for a motor vehicle (40), comprising the steps: - receiving (50) at least one history of positions and a direction of movement of the motor vehicle (40); - determining (51) information on traffic regulations applicable at the position of the motor vehicle (40); and - transmitting (52) the information on the traffic regulations applicable at the position of the motor vehicle (40) to the motor vehicle (40); wherein the information on the traffic regulations applicable at the position of the motor vehicle (40) comprises information on the validity of the traffic regulations, and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted. [3] Method according to claim 2, wherein determining (51) the information on the traffic regulations applicable at the position of the motor vehicle (40) comprises the steps of: - Assigning (60) the position of the motor vehicle (40) to a road in a road network; - determining (61) traffic rules applicable to the road at the position of the motor vehicle (40); and - Determining (62) at least one distance in the road network until a change in the applicable traffic rules. [4] Method according to one of claims 1 to 3, wherein the information on the validity of the traffic rules comprises an indicator indicating that the position of the motor vehicle (40) is in or adjacent to an intersection area. [5] Method according to claim 4, wherein an increased cycle frequency is used for transmitting (11) at least a history of positions and a direction of movement of the motor vehicle (40) to the backend (90) when the position of the motor vehicle (40) is in or adjacent to an intersection area. [6] Method according to one of claims 1 to 3, wherein the information on the validity of the traffic rules describes a spatial validity, in particular a spatial validity dependent on a route. [7] Method according to claim 6, wherein the transmission (11) of at least one history of positions and a direction of movement of the motor vehicle (40) to the backend (90) is carried out again upon expiration of the spatial validity. [8] Method according to one of the preceding claims, wherein the information on the traffic regulations applicable at the position of the motor vehicle (40) comprises detailed information on at least one intersection. [9] Method according to one of the preceding claims, wherein the traffic regulations applicable at the position of the motor vehicle (40) describe a speed limit, a right of way or a prohibition of overtaking. [10] A computer-readable storage medium having instructions which, when executed by a computer, cause the computer to carry out the steps of a method according to any one of claims 1 to 9 for determining applicable traffic rules for a motor vehicle (40). [11] Device (20) for determining applicable traffic rules for a motor vehicle (40), comprising: - a transmission device (23) for transmitting (11) at least one history of positions and a direction of movement of the motor vehicle (40) to a backend (90) and for receiving (12) information on traffic regulations applicable at the position of the motor vehicle (40); and - a data processing unit (24) for evaluating the information on the traffic regulations applicable at the position of the motor vehicle (40); wherein the transmission device (23) is configured to transmit (11) at least one history of positions and a direction of movement of the motor vehicle (40) to the backend (90) cyclically or as a function of information on a validity of the traffic regulations contained in the information on the traffic regulations applicable at the position of the motor vehicle (40), and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted. [12] Device (70) for determining applicable traffic rules for a motor vehicle (40), comprising: - a transmission device (72) for receiving (50) at least one history of positions and a direction of movement of the motor vehicle (40) and for transmitting (52) information on traffic regulations applicable at the position of the motor vehicle (40) to the motor vehicle (40); and - a computing unit (74) for determining (51) the information on the traffic regulations applicable at the position of the motor vehicle (40); wherein the computing unit (74) is configured to provide the information on the traffic regulations applicable at the position of the motor vehicle (40) with information on the validity of the traffic regulations, and wherein, in the history of positions, positions immediately before and after a lane change or positions with steering angle changes are preferentially transmitted. [13] Motor vehicle (40), wherein the motor vehicle (40) comprises a device (20) according to claim 11 or is configured to carry out a method according to one of claims 1 to 2 or 5 to 9 for determining applicable traffic rules.

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